1. Field of the Invention
The present invention relates to an information communication apparatus having cipher processing function, a method, an information communication system and a memory medium therefor.
2. Related Background Art
The information communication apparatus, represented by mobile communication terminal, has shown remarkable progress in compactization, higher performance and higher speed in information processing, and there are already commercialized mobile communication terminals that are comparable in performance to the desk-top computers. Because of such tendency, the mobile communication terminals are rapidly becoming popular in the business field, in enabling rapid information exchange by wireless communication even when one is not in the office. In such form of communication, the leak of secrecy is always a major concern. Therefore the corporations engaged in the development of the information communication apparatus are actively the development of cipher process technology of the transmitted information.
On the other hand, the amount of the processed information is rapidly growing, such as taking, fetching and transmitting the digital image in the communication function, and the performance required for the information signal processing unit will become even larger, as the moving image will also be processed in the future. Furthermore, the mobile communication terminal integrating the digital camera for image fetching has been recently commercialized and the mobile communication terminal including the digital video camera will also appear in the near future.
However, because of such advancement in the performance of the mobile information terminal, it is increasingly becoming difficult to achieve compactization important for mobility, in comparison with the conventional products provided solely with the communication function of the information editing function. In order to additionally include the cipher process in the above-described situation, it is important not only to increase the information processing speed but also to reduce the dimension of the entire information communication apparatus including the cipher processing device.
As explained in the foregoing, the current issues associated with the information communication apparatus are the cost increase resulting from the increase in the performance, the enormous increase in the amount of information to be handled, including images, and the difficulty in compactization particularly in the mobile terminal or the like.
Also the apparatus capable of cipher process is recently attracting attention, and various communication apparatus with the enciphering means are expected to be commercialized in the future. On the other hand, in the home use, the level of secrecy of the information to be handled is relatively low, so that the enciphering process may not be essential. However, if the enciphered information is always transmitted, the receiving side has to be equipped with the deciphering device for reading the enciphered information. As a result, the increase in the dimension of the apparatus, in the cost and in the burden for the information processing is unavoidable in the transmitting side and in the receiving side.